1. Technical Field
The present disclosure relates to a digital communication field, particularly to a communication system technology in which a rotation constellation and a plurality of frequency channels are used together with a quasi-cyclic low-density parity check (QC LDPC) code.
2. Description of the Related Art
Conventionally, there is a communication system in which rotation constellation is used and data is transmitted and received with the plurality of frequency channels switched (for example, see PTL 1).
For example, a transmitter in the communication system converts a codeword based on the quasi-cyclic low-density parity check (QC LDPC) code into a plurality of components. D components are grouped, and a square orthogonal matrix of D rows and D columns is multiplied by a D-dimensional vector (D-dimensional constellation block) in which the D components are set to each dimensional value in each group (rotation processing).
The transmitter allocates D rotation components of the D-dimensional vector (each D-dimensional rotation constellation block), which is subjected to the rotation processing, to the plurality of frequency channels in order to obtain channel diversity.